## LifeIsADangerousGame 2 years ago Help with Slope?

1. Directrix

Is there a problem to work?

Yea, here is it I already have my answer for it -3/4 is that correct?

3. electrokid

m=(1-3)/(4-0)= -2/4= -1/2

4. phi

@electrokid Can you explain how you did that ?

5. electrokid

well, i took each grid as "1" unit m=(y2-y1)/(x2-x1) it is a st line so, should be same

6. electrokid

oh.. i took the y-intercept as "3" instead of "4".. got ya so, it is "-3/4"

7. electrokid

eyes are deceptive

@phi what does it mean to solve for y in terms of x? And how do I figure out the slope of a line with some like y=(-3/4)x-2?

9. phi

two questions if you are given y = mx +b form (in other words you see y = number times x plus another number the number in front of the x (the coefficient of the x term) is the slope (that is why people put the equation in this form, so they can "read off" the slope

10. phi

solve for y in terms of x that means do algebra so y is on the left side of the = and everything else is on the right side for example if you had 3x+4y= -8 that is the equation of a line. But it is not obvious what its slope is. if we solve for y, we would do this: add -3x to both sides 3x-3x + 4y= -3x -8 or 4y= -3x-8 (that step "moved" 3x to the right side) now divide both sides by 4 (both sides, all terms) 4y/4 = -3x/4 -8/4 y= (-3/4)x -2 we have solved for y in terms of x

So for something like 6x+3y=81 it would be 6x+3y=81 -6x -6x 3y/3 = - 6x/3 - 81/3 y = - 6x/3 - 81/3 y = -2x - 27?

actually, I messed it up, one moment

6x+3y=81 -6x -6x 3y/3 = - 6x/3 + 81/3 y = - 6x/3 + 81/3 y = -2x + 27? That should be correct

14. phi

yes, perfect. slope is -2 and y-intercept is 27

:D Awesome, I'm gonna go try it out a little

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